ive got a small 5.X cubic foot Chest freezer that i added a 12" collar to. It fits 2 x 6.5 gal carboys no problem. and will get down to the temp i need if im gunna lager.
picked it up for $45 on Craigslist.
see similar items/prices on CL a few times a month.
and +1 for the Ebay Temp controller